Continuous motion washing machines, such as pot and pan washing machines of the type used in restaurants, institutions and other eating facilities, often involve a large wash tank or basin in which fluid is circulated to provide a rolling wash action for the pots, pans or other items being washed. One such machine is described in U.S. Pat. No. 4,773,436 issued to Cantrell et al., the entire disclosure of which is incorporated herein by reference. The machine of Cantrell includes a wash tank with multiple jets evenly spaced apart at an elevated position along the rear wall of the wash tank. The tank is filled with water (or other suitable wash fluid) to a level above the position of the jets. Pots and pans are placed in the wash tank, and a pump is activated to draw fluid from within the wash tank and direct it through the jets to create a jet stream. Each jet directs its jet stream toward the bottom wall of the wash tank, the bottom wall then deflects the jet stream upward and towards the front wall of the tank. The front wall then deflects the upward moving jet stream towards the rear wall of the tank, and the rear wall deflects the jet stream downward and back towards the front wall along the bottom wall. The combination of deflections of the jet stream from the bottom, front and rear walls provides a rolling washing action within the wash tank.
The basic components of the wash tank of the pot and pan washing machine of the prior art are shown FIG. 1. Wash tank 10 includes end walls 12 and 14, rear side long wall 16, front side long wall 18 and bottom wall 19. A pump can be attached to either end wall; in the embodiment shown in FIG. 1, pump 50 is attached to right end wall 14. An impeller located within pump 50 is driven by electric motor 56. The impeller draws fluid into pump inlet 52 through an intake port (not shown) located in end wall 14. The fluid is then discharged from the pump through pump outlet 54 and into outlet manifold 60. Outlet manifold 60 includes a ninety degree turn, and several other turns, to direct the fluid across the back side of rear wall 16 and out jet nozzles 20 (“flow directional openings”) which are protruding through and extending from rear wall 16. The intake port associated with pump inlet 52 is covered by perforated (holes, voids, mesh, etc.) intake manifold 30. Intake manifold 30 includes handle 36 and is removably supported within wash tank 10 for easy cleaning. Intake manifold 30 fits tightly between outer runner 32 and inner runner 34, each of which extends vertically from bottom wall 19. Heating element 40 is positioned between intake manifold 30 and end wall 14 for its protection and to maximize the use of space.
Although the prior art pot and pan washing machine disclosed in U.S. Pat. No. 4,773,436 provides an exceptional wash action, many of the components discussed above hinder the overall efficiency and performance of the machine. The inventions disclosed in U.S. Pat. Nos. 6,739,348, 7,162,788, 6,976,496, 7,246,624, 7,523,757, and 6,609,259, the entire disclosures of which are incorporated herein by reference, provide components that greatly increase the overall efficiency and performance of the machine, including improvements to the intake and discharge manifolds, jets, pump, drain, at system assembly methods. The inventions disclosed in U.S. patent application Ser. No. 12/781,750 (Application Pub. No. US 2011-0120503 A1), the entire disclosure of which is incorporated herein by reference, provide improved rinsing and/or sanitizing systems and methods for washing machines. In addition, international Patent Application PCT/US09/59600 (Application Pub. No. WO 2010/040149) and U.S. patent application Ser. No. 13/080,453 (Application Pub. No. US 2011-0240062 A1), the entire disclosures of which are incorporated herein by reference, provides a condition warning system, control system and control methods for a pot and pan washing machine that addresses a number of disadvantages in typical condition warning systems, control systems and control methods for such machines. U.S. patent application Ser. No. 13/021,682 (US 2011-0240061 A1), the entire disclosure of which is incorporated herein by reference, provides control systems and control methods for a pot and pan washing machine that address yet other disadvantages in typical control systems and methods for such machine. Further in addition, U.S. patent application Ser. No. 12/765,838 (Application Pub. No. US 2011-0017241 A1, the “AWI Application”), the entire disclosure of which is incorporated herein by reference, provides a wash tank insert that greatly improves the wash action within the wash tank and reduces impacts, noise and other vibrations acting on the walls of the wash tank. Notwithstanding these many improvements, the circulating wash action of these types of machines, causes a considerable amount of generally continuous force upon components of the machine due to multiple impacts of pots, pans and/or other items being circulated within the wash fluid. In particular, it has been discovered that this generally continuous force tends to cause material creep within (or expansion of) certain components, such as in certain embodiments of the wash tank insert of the AWI Application. This expansion results in the components eventually not fitting together properly, more difficultly, and/or no longer within the wash tank. Therefore, it would be beneficial to provide a wash tank insert system and methods that takes into account and/or reduces the detrimental effects as creep occurs.